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1.
Cell ; 181(3): 590-603.e16, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32272060

RESUMO

Conversion of glial cells into functional neurons represents a potential therapeutic approach for replenishing neuronal loss associated with neurodegenerative diseases and brain injury. Previous attempts in this area using expression of transcription factors were hindered by the low conversion efficiency and failure of generating desired neuronal types in vivo. Here, we report that downregulation of a single RNA-binding protein, polypyrimidine tract-binding protein 1 (Ptbp1), using in vivo viral delivery of a recently developed RNA-targeting CRISPR system CasRx, resulted in the conversion of Müller glia into retinal ganglion cells (RGCs) with a high efficiency, leading to the alleviation of disease symptoms associated with RGC loss. Furthermore, this approach also induced neurons with dopaminergic features in the striatum and alleviated motor defects in a Parkinson's disease mouse model. Thus, glia-to-neuron conversion by CasRx-mediated Ptbp1 knockdown represents a promising in vivo genetic approach for treating a variety of disorders due to neuronal loss.


Assuntos
Neurogênese/fisiologia , Neuroglia/metabolismo , Células Ganglionares da Retina/metabolismo , Animais , Sistemas CRISPR-Cas/fisiologia , Diferenciação Celular/fisiologia , Células Cultivadas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Modelos Animais de Doenças , Dopamina/metabolismo , Regulação da Expressão Gênica/genética , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doenças do Sistema Nervoso/metabolismo , Neurônios/metabolismo , Doença de Parkinson/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Células Ganglionares da Retina/fisiologia
2.
Nature ; 623(7988): 724-731, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37938779

RESUMO

Nanomaterials must be systematically designed to be technologically viable1-5. Driven by optimizing intermolecular interactions, current designs are too rigid to plug in new chemical functionalities and cannot mitigate condition differences during integration6,7. Despite extensive optimization of building blocks and treatments, accessing nanostructures with the required feature sizes and chemistries is difficult. Programming their growth across the nano-to-macro hierarchy also remains challenging, if not impossible8-13. To address these limitations, we should shift to entropy-driven assemblies to gain design flexibility, as seen in high-entropy alloys, and program nanomaterial growth to kinetically match target feature sizes to the mobility of the system during processing14-17. Here, following a micro-then-nano growth sequence in ternary composite blends composed of block-copolymer-based supramolecules, small molecules and nanoparticles, we successfully fabricate high-performance barrier materials composed of more than 200 stacked nanosheets (125 nm sheet thickness) with a defect density less than 0.056 µm-2 and about 98% efficiency in controlling the defect type. Contrary to common perception, polymer-chain entanglements are advantageous to realize long-range order, accelerate the fabrication process (<30 min) and satisfy specific requirements to advance multilayered film technology3,4,18. This study showcases the feasibility, necessity and unlimited opportunities to transform laboratory nanoscience into nanotechnology through systems engineering of self-assembly.

3.
Proc Natl Acad Sci U S A ; 121(44): e2414437121, 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39453740

RESUMO

The clearance of senescent and altered red blood cells (RBCs) in the red pulp of the human spleen involves sequential processes of prefiltration, filtration, and postfiltration. While prior work has elucidated the mechanisms underlying the first two processes, biomechanical processes driving the postfiltration phagocytosis of RBCs retained at interendothelial slits (IES) are still poorly understood. We present here a unique computational model of macrophages to study the role of cell biomechanics in modulating the kinetics of phagocytosis of aged and diseased RBCs retained in the spleen. After validating the macrophage model using in vitro phagocytosis experiments, we employ it to probe the mechanisms underlying the kinetics of phagocytosis of mechanically altered RBCs, such as heated RBCs and abnormal RBCs in hereditary spherocytosis (HS) and sickle cell disease (SCD). Our simulations show pronounced deformation of the flexible and healthy RBCs in contrast to minimal shape changes in altered RBCs. Simulations also show that less deformable RBCs are engulfed faster and at lower adhesive strength than flexible RBCs, consistent with our experimental measurements. This efficient sensing and engulfment by macrophages of stiff RBCs retained at IES are expected to temper splenic congestion, a common pathogenic process in malaria, HS, and SCD. Altogether, our combined computational and in vitro experimental studies suggest that mechanical alterations of retained RBCs may suffice to enhance their phagocytosis, thereby adapting the kinetics of their elimination to the kinetics of their mechanical retention, an equilibrium essential for adequately cleaning the splenic filter to preserve its function.


Assuntos
Eritrócitos , Macrófagos , Fagocitose , Baço , Humanos , Macrófagos/fisiologia , Baço/citologia , Fenômenos Biomecânicos , Anemia Falciforme/patologia , Esferocitose Hereditária/patologia , Modelos Biológicos
4.
Brief Bioinform ; 25(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38343327

RESUMO

Hyperactive ribosome biogenesis (RiboSis) fuels unrestricted cell proliferation, whereas genomic hallmarks and therapeutic targets of RiboSis in cancers remain elusive, and efficient approaches to quantify RiboSis activity are still limited. Here, we have established an in silico approach to conveniently score RiboSis activity based on individual transcriptome data. By employing this novel approach and RNA-seq data of 14 645 samples from TCGA/GTEx dataset and 917 294 single-cell expression profiles across 13 cancer types, we observed the elevated activity of RiboSis in malignant cells of various human cancers, and high risk of severe outcomes in patients with high RiboSis activity. Our mining of pan-cancer multi-omics data characterized numerous molecular alterations of RiboSis, and unveiled the predominant somatic alteration in RiboSis genes was copy number variation. A total of 128 RiboSis genes, including EXOSC4, BOP1, RPLP0P6 and UTP23, were identified as potential therapeutic targets. Interestingly, we observed that the activity of RiboSis was associated with TP53 mutations, and hyperactive RiboSis was associated with poor outcomes in lung cancer patients without TP53 mutations, highlighting the importance of considering TP53 mutations during therapy by impairing RiboSis. Moreover, we predicted 23 compounds, including methotrexate and CX-5461, associated with the expression signature of RiboSis genes. The current study generates a comprehensive blueprint of molecular alterations in RiboSis genes across cancers, which provides a valuable resource for RiboSis-based anti-tumor therapy.


Assuntos
Variações do Número de Cópias de DNA , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Genômica , Mutação , Ribossomos/genética , Ribossomos/metabolismo , Proteínas de Ligação a RNA/genética
5.
Nucleic Acids Res ; 52(4): e18, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38153174

RESUMO

Homozygous duplications contribute to genetic disease by altering gene dosage or disrupting gene regulation and can be more deleterious to organismal biology than heterozygous duplications. Intragenic exonic duplications can result in loss-of-function (LoF) or gain-of-function (GoF) alleles that when homozygosed, i.e. brought to homozygous state at a locus by identity by descent or state, could potentially result in autosomal recessive (AR) rare disease traits. However, the detection and functional interpretation of homozygous duplications from exome sequencing data remains a challenge. We developed a framework algorithm, HMZDupFinder, that is designed to detect exonic homozygous duplications from exome sequencing (ES) data. The HMZDupFinder algorithm can efficiently process large datasets and accurately identifies small intragenic duplications, including those associated with rare disease traits. HMZDupFinder called 965 homozygous duplications with three or less exons from 8,707 ES with a recall rate of 70.9% and a precision of 16.1%. We experimentally confirmed 8/10 rare homozygous duplications. Pathogenicity assessment of these copy number variant alleles allowed clinical genomics contextualization for three homozygous duplications alleles, including two affecting known OMIM disease genes EDAR (MIM# 224900), TNNT1(MIM# 605355), and one variant in a novel candidate disease gene: PAAF1.


Assuntos
Variações do Número de Cópias de DNA , Sequenciamento do Exoma , Software , Humanos , Proteínas Adaptadoras de Transdução de Sinal , Homozigoto , Doenças Raras/genética
6.
Proc Natl Acad Sci U S A ; 120(9): e2217081120, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36812199

RESUMO

Carbon capture is one of the essential low-carbon technologies required to achieve societal climate goals at the lowest cost. Covalent organic frameworks (COFs) are promising adsorbents for CO2 capture because of their well-defined porosity, large surface area, and high stability. Current COF-based CO2 capture is mainly based on a physisorption mechanism, exhibiting smooth and reversible sorption isotherms. In the present study, we report unusual CO2 sorption isotherms featuring one or more tunable hysteresis steps with metal ion (Fe3+, Cr3+, or In3+)-doped Schiff-base two-dimensional (2D) COFs (Py-1P, Py-TT, and Py-Py) as adsorbents. Synchrotron X-ray diffraction, spectroscopic and computational studies indicate that the sharp adsorption steps in the isotherm originate from the insertion of CO2 between the metal ion and the N atom of the imine bond on the inner pore surface of the COFs as the CO2 pressure reaches threshold values. As a result, the CO2 adsorption capacity of the ion-doped Py-1P COF is increased by 89.5% compared with that of the undoped Py-1P COF. This CO2 sorption mechanism provides an efficient and straightforward approach to enhancing the CO2 capture capacity of COF-based adsorbents, yielding insights into developing chemistry for CO2 capture and conversion.

7.
Plant J ; 117(4): 1130-1147, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37967025

RESUMO

Flowering is an indicator of plant transformation from vegetative to reproductive growth. miR160 has been shown to have a significant effect on the growth and development of fruits, leaves, and roots of plants or their stress response to environment, but the participation of miR160 in regulating flowering time in plants is unclear. In this study, we found that two FvemiR160s (FvemiR160a/FvemiR160b) mature sequences in strawberry (Fragaria vesca) were consistent. It was displayed that the miR160 mature sequence is highly conserved in various species, and the miR160 mature sequence formed by the 5' arm of the MIR160 precursor was more conserved. Three FveARFs in woodland strawberry were negatively regulated by FvemiR160a, among which FveARF18A was the most significant. Phylogenetic analysis indicated that FvemiR160 is closely related to apple (Malus domestica), grape (Vitis vinifera), and Arabidopsis thaliana, while FveARF18A is closely related to RcARF18. Subsequently, we demonstrated that FvemiR160a can target cutting FveARF18A to negatively regulate its expression by RLM-5' RACE, cleavage site mutation, and GFP fluorescence assay. Moreover, we observed that FveMIR160a overexpressed plants have advanced flowering, while mFveARF18A overexpressed plants have delayed flowering. We also verified that FveARF18A negatively regulates the expression of FveAP1 and FveFUL by binding their promoters by yeast one-hybrid, LUC, and GUS assay, and FveAP1 and FveFUL transgenic Arabidopsis showed early flowering phenotype. In addition, the expression level of FvemiR160a was decreased obviously while that of FveARF18A was increased obviously by MeJA, GA and IAA. In conclusion, our study reveals the important role of the FvemiR160-FveARF18A-FveAP1/FveFUL module in the flowering process of woodland strawberry and provides a new pathway for studying flowering.


Assuntos
Fragaria , Fragaria/genética , Fragaria/metabolismo , Filogenia , Folhas de Planta/genética , Fenótipo , Regiões Promotoras Genéticas , Regulação da Expressão Gênica de Plantas/genética
8.
Blood ; 142(17): 1494-1499, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37624915

RESUMO

Here we report a new fusion gene, STRN3-RARA, in acute promyelocytic leukemia (APL). It cooperates with UTX deficiency to drive full-blown APL in mice. Although STRN3-RARA leukemia quickly relapses after all-trans retinoic acid treatment, it can be restrained by cepharanthine.


Assuntos
Leucemia Promielocítica Aguda , Animais , Camundongos , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/genética , Proteínas de Fusão Oncogênica/genética , Tretinoína/uso terapêutico
9.
Mol Psychiatry ; 29(7): 2170-2184, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38454083

RESUMO

Both peripheral and central corticotropin-releasing factor (CRF) systems have been implicated in regulating pain sensation. However, compared with the peripheral, the mechanisms underlying central CRF system in pain modulation have not yet been elucidated, especially at the neural circuit level. The corticoaccumbal circuit, a structure rich in CRF receptors and CRF-positive neurons, plays an important role in behavioral responses to stressors including nociceptive stimuli. The present study was designed to investigate whether and how CRF signaling in this circuit regulated pain sensation under physiological and pathological pain conditions. Our studies employed the viral tracing and circuit-, and cell-specific electrophysiological methods to label the CRF-containing circuit from the medial prefrontal cortex to the nucleus accumbens shell (mPFCCRF-NAcS) and record its neuronal propriety. Combining optogenetic and chemogenetic manipulation, neuropharmacological methods, and behavioral tests, we were able to precisely manipulate this circuit and depict its role in regulation of pain sensation. The current study found that the CRF signaling in the NAc shell (NAcS), but not NAc core, was necessary and sufficient for the regulation of pain sensation under physiological and pathological pain conditions. This process was involved in the CRF-mediated enhancement of excitatory synaptic transmission in the NAcS. Furthermore, we demonstrated that the mPFCCRF neurons monosynaptically connected with the NAcS neurons. Chronic pain increased the protein level of CRF in NAcS, and then maintained the persistent NAcS neuronal hyperactivity through enhancement of this monosynaptic excitatory connection, and thus sustained chronic pain behavior. These findings reveal a novel cell- and circuit-based mechanistic link between chronic pain and the mPFCCRF → NAcS circuit and provide a potential new therapeutic target for chronic pain.


Assuntos
Hormônio Liberador da Corticotropina , Neurônios , Núcleo Accumbens , Córtex Pré-Frontal , Transmissão Sináptica , Hormônio Liberador da Corticotropina/metabolismo , Animais , Núcleo Accumbens/metabolismo , Transmissão Sináptica/fisiologia , Masculino , Neurônios/metabolismo , Neurônios/fisiologia , Córtex Pré-Frontal/metabolismo , Dor/metabolismo , Dor/fisiopatologia , Camundongos , Optogenética/métodos , Vias Neurais/metabolismo , Vias Neurais/fisiologia , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Camundongos Endogâmicos C57BL
10.
Proc Natl Acad Sci U S A ; 119(32): e2200879119, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35925889

RESUMO

The value of anti-CTLA-4 antibodies in cancer therapy is well established. However, the broad application of currently available anti-CTLA-4 therapeutic antibodies is hampered by their narrow therapeutic index. It is therefore challenging and attractive to develop the next generation of anti-CTLA-4 therapeutics with improved safety and efficacy. To this end, we generated fully human heavy chain-only antibodies (HCAbs) against CTLA-4. The hIgG1 Fc domain of the top candidate, HCAb 4003-1, was further engineered to enhance its regulatory T (Treg) cell depletion effect and to decrease its half-life, resulting in HCAb 4003-2. We tested these HCAbs in in vitro and in vivo experiments in comparison with ipilimumab and other anti-CTLA4 antibodies. The results show that human HCAb 4003-2 binds human CTLA-4 with high affinity and potently blocks the binding of B7-1 (CD80) and B7-2 (CD86) to CTLA-4. The results also show efficient tumor penetration. HCAb 4003-2 exhibits enhanced antibody-dependent cellular cytotoxicity function, lower serum exposure, and more potent anti-tumor activity than ipilimumab in murine tumor models, which is partly driven by a substantial depletion of intratumoral Tregs. Importantly, the enhanced efficacy combined with the shorter serum half-life and less systemic drug exposure in vivo potentially provides an improved therapeutic window in cynomolgus monkeys and preliminary clinical applications. With its augmented efficacy via Treg depletion and improved safety profile, HCAb 4003-2 is a promising candidate for the development of next generation anti-CTLA-4 therapy.


Assuntos
Cadeias Pesadas de Imunoglobulinas , Imunoterapia , Neoplasias , Linfócitos T Reguladores , Animais , Citotoxicidade Celular Dependente de Anticorpos , Antígeno CTLA-4/imunologia , Humanos , Cadeias Pesadas de Imunoglobulinas/farmacologia , Ipilimumab/farmacologia , Camundongos , Neoplasias/patologia , Neoplasias/terapia
11.
Nano Lett ; 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39356651

RESUMO

High-performance separation materials for oil-water emulsions are crucial to environmental protection and resource recovery; however, most existing fibrous separation materials are subject to large pore size and low porosity, resulting in limited separation performance. Herein, we create high-performance membranes consisting of spherical-beaded nanofibers and nanoarchitectured networks (nano-nets) using electrostatic spinning/netting technology, for water-in-oil emulsion separation. By manipulating the nonequilibrium stretching of jets, spherical-beaded nanofibers capable of generating a robust microelectric field are fabricated as scaffolds, on which charged droplets are induced to eject and phase separate to self-assemble nano-nets with small pores. Benefiting from 3D undulating networks with cavities originating from 2D nano-nets supported by 1D spherical-beaded nanofibers, the membranes exhibit under-oil superhydrophobicity (>152°), a striking separation performance with an efficiency of >99.2% and a flux of 5775 L m-2 h-1, together with wide pressure applicability, antifouling, and reusability. This work may open up new horizons in developing fibrous materials for separation and purification.

12.
Biophys J ; 123(9): 1069-1084, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38532625

RESUMO

Macrophage phagocytosis is critical for the immune response, homeostasis regulation, and tissue repair. This intricate process involves complex changes in cell morphology, cytoskeletal reorganization, and various receptor-ligand interactions controlled by mechanical constraints. However, there is a lack of comprehensive theoretical and computational models that investigate the mechanical process of phagocytosis in the context of cytoskeletal rearrangement. To address this issue, we propose a novel coarse-grained mesoscopic model that integrates a fluid-like cell membrane and a cytoskeletal network to study the dynamic phagocytosis process. The growth of actin filaments results in the formation of long and thin pseudopods, and the initial cytoskeleton can be disassembled upon target entry and reconstructed after phagocytosis. Through dynamic changes in the cytoskeleton, our macrophage model achieves active phagocytosis by forming a phagocytic cup utilizing pseudopods in two distinct ways. We have developed a new algorithm for modifying membrane area to prevent membrane rupture and ensure sufficient surface area during phagocytosis. In addition, the bending modulus, shear stiffness, and cortical tension of the macrophage model are investigated through computation of the axial force for the tubular structure and micropipette aspiration. With this model, we simulate active phagocytosis at the cytoskeletal level and investigate the mechanical process during the dynamic interplay between macrophage and target particles.


Assuntos
Macrófagos , Modelos Biológicos , Fagocitose , Pseudópodes , Macrófagos/citologia , Macrófagos/metabolismo , Pseudópodes/metabolismo , Membrana Celular/metabolismo , Fenômenos Biomecânicos , Citoesqueleto/metabolismo
13.
J Cell Mol Med ; 28(9): e18274, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38676362

RESUMO

TRP channels, are non-specific cationic channels that are involved in multiple physiological processes that include salivation, cellular secretions, memory extinction and consolidation, temperature, pain, store-operated calcium entry, thermosensation and functionality of the nervous system. Here we choose to look at the evidence that decisively shows how TRP channels modulate human neuron plasticity as it relates to the molecular neurobiology of sleep/circadian rhythm. There are numerous model organisms of sleep and circadian rhythm that are the results of the absence or genetic manipulation of the non-specific cationic TRP channels. Drosophila and mice that have had their TRP channels genetically ablated or manipulated show strong evidence of changes in sleep duration, sleep activity, circadian rhythm and response to temperature, noxious odours and pattern of activity during both sleep and wakefulness along with cardiovascular and respiratory function during sleep. Indeed the role of TRP channels in regulating sleep and circadian rhythm is very interesting considering the parallel roles of TRP channels in thermoregulation and thermal response with concomitant responses in growth and degradation of neurites, peripheral nerves and neuronal brain networks. TRP channels provide evidence of an ability to create, regulate and modify our sleep and circadian rhythm in a wide array of physiological and pathophysiological conditions. In the current review, we summarize previous results and novel recent advances in the understanding of calcium ion entry via TRP channels in different sleep and circadian rhythm conditions. We discuss the role of TRP channels in sleep and circadian disorders.


Assuntos
Ritmo Circadiano , Sono , Canais de Potencial de Receptor Transitório , Ritmo Circadiano/fisiologia , Ritmo Circadiano/genética , Animais , Humanos , Sono/fisiologia , Canais de Potencial de Receptor Transitório/metabolismo , Canais de Potencial de Receptor Transitório/genética
14.
J Cell Mol Med ; 28(16): e70004, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39159174

RESUMO

Ischemia and hypoxia activate astrocytes into reactive types A1 and A2, which play roles in damage and protection, respectively. However, the function and mechanism of A1 and A2 astrocyte exosomes are unknown. After astrocyte exosomes were injected into the lateral ventricle, infarct volume, damage to the blood-brain barrier (BBB), apoptosis and the expression of microglia-related proteins were measured. The dual luciferase reporter assay was used to detect the target genes of miR-628, and overexpressing A2-Exos overexpressed and knocked down miR-628 were constructed. qRT-PCR, western blotting and immunofluorescence staining were subsequently performed. A2-Exos obviously reduced the infarct volume, damage to the BBB and apoptosis and promoted M2 microglial polarization. RT-PCR showed that miR-628 was highly expressed in A2-Exos. Dual luciferase reporter assays revealed that NLRP3, S1PR3 and IRF5 are target genes of miR-628. After miR-628 was overexpressed or knocked down, the protective effects of A2-Exos increased or decreased, respectively. A2-Exos reduced pyroptosis and BBB damage and promoted M2 microglial polarization through the inhibition of NLRP3, S1PR3 and IRF5 via the delivery of miR-628. This study explored the mechanism of action of A2-Exos and provided new therapeutic targets and concepts for treating cerebral ischemia.


Assuntos
Astrócitos , Barreira Hematoencefálica , Isquemia Encefálica , Exossomos , MicroRNAs , Traumatismo por Reperfusão , MicroRNAs/genética , MicroRNAs/metabolismo , Animais , Astrócitos/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/terapia , Exossomos/metabolismo , Isquemia Encefálica/metabolismo , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Isquemia Encefálica/patologia , Barreira Hematoencefálica/metabolismo , Masculino , Apoptose/genética , Microglia/metabolismo , Microglia/patologia , Camundongos
15.
BMC Genomics ; 25(1): 328, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38566015

RESUMO

BACKGROUND: Whole-genome duplication and long terminal repeat retrotransposons (LTR-RTs) amplification in organisms are essential factors that affect speciation, local adaptation, and diversification of organisms. Understanding the karyotype projection and LTR-RTs amplification could contribute to untangling evolutionary history. This study compared the karyotype and LTR-RTs evolution in the genomes of eight oaks, a dominant lineage in Northern Hemisphere forests. RESULTS: Karyotype projections showed that chromosomal evolution was relatively conservative in oaks, especially on chromosomes 1 and 7. Modern oak chromosomes formed through multiple fusions, fissions, and rearrangements after an ancestral triplication event. Species-specific chromosomal rearrangements revealed fragments preserved through natural selection and adaptive evolution. A total of 441,449 full-length LTR-RTs were identified from eight oak genomes, and the number of LTR-RTs for oaks from section Cyclobalanopsis was larger than in other sections. Recent amplification of the species-specific LTR-RTs lineages resulted in significant variation in the abundance and composition of LTR-RTs among oaks. The LTR-RTs insertion suppresses gene expression, and the suppressed intensity in gene regions was larger than in promoter regions. Some centromere and rearrangement regions indicated high-density peaks of LTR/Copia and LTR/Gypsy. Different centromeric regional repeat units (32, 78, 79 bp) were detected on different Q. glauca chromosomes. CONCLUSION: Chromosome fusions and arm exchanges contribute to the formation of oak karyotypes. The composition and abundance of LTR-RTs are affected by its recent amplification. LTR-RTs random retrotransposition suppresses gene expression and is enriched in centromere and chromosomal rearrangement regions. This study provides novel insights into the evolutionary history of oak karyotypes and the organization, amplification, and function of LTR-RTs.


Assuntos
Quercus , Retroelementos , Quercus/genética , Genoma de Planta , Cariótipo , Sequências Repetidas Terminais/genética , Evolução Molecular , Filogenia
16.
BMC Genomics ; 25(1): 133, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38302866

RESUMO

BACKGROUND: WD40 proteins, which are highly prevalent in eukaryotes, play important roles in plant development and stress responses. However, systematic identification and exploration of WD40 proteins in tobacco have not yet been conducted. RESULTS: In this study, a total of 399 WD40 regulatory genes were identified in common tobacco (Nicotiana tabacum). Gene structure and motif analysis revealed structural and functional diversity among different clades of tobacco WD40 regulatory genes. The expansion of tobacco WD40 regulatory genes was mainly driven by segmental duplication and purifying selection. A potential regulatory network of NtWD40s suggested that NtWD40s might be regulated by miRNAs and transcription factors in various biological processes. Expression pattern analysis via transcriptome analysis and qRT-PCR revealed that many NtWD40s exhibited tissue-specific expression patterns and might be involved in various biotic and abiotic stresses. Furthermore, we have validated the critical role of NtTTG1, which was located in the nuclei of trichome cells, in enhancing the drought tolerance of tobacco plants. CONCLUSIONS: Our study provides comprehensive information to better understand the evolution of WD40 regulatory genes and their roles in different stress responses in tobacco.


Assuntos
Resistência à Seca , Nicotiana , Nicotiana/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Perfilação da Expressão Gênica , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Filogenia
17.
J Cell Biochem ; : e30659, 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39370596

RESUMO

Decreased regenerative capacity of central nervous system neurons is the main cause for failure of damaged neuron regeneration and functional recovery. Long noncoding RNAs (lncRNAs) are abundant in mammalian transcriptomes, and many time- and tissue-specific lncRNAs are thought to be closely related to specific biological functions. The promoting effect of Pim-1 gene on neural differentiation and regeneration has been documented, but the effect and mechanism of its neighbor gene Lnc-Pim1 in regulating the response of central neurons to injury remain unclear. RT-PCR in this study demonstrated that the expression of Lnc-Pim1 was upregulated in acrylamide (ACR)-induced neuronal injury. FISH and nucleus-cytoplasmic assay demonstrated that Lnc-Pim1 was mainly expressed in the neuron cytoplasm, with a small amount in the nucleus. Western blot analysis proved that Lnc-Pim1 overexpression induced by the lentivirus vector could promote neurite outgrowth in Neuro-2a cells by activating the Erk1/2 signal pathway, and improve neurite regeneration of injured neurons by upregulating GAP-43 and ß-Ⅲ tubulin protein expression. However, silencing Lnc-Pim1 expression by interfering RNA could effectively downregulate the GAP-43 and ß-Ⅲ tubulin protein expression, and inhibit neurite growth of neurons. In addition, CHIRP-MS was performed to identify several potential targets of Lnc-Pim1 involved in the regulation of neurite regeneration of injured neurons. In conclusion, our study demonstrated that Lnc-Pim1 is a potential lnc-RNA, playing an important role in regulating central nerve regeneration.

18.
J Am Chem Soc ; 146(21): 14433-14438, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38757701

RESUMO

Homochiral MOF membranes offer a promising route to efficient chiral separation, but their fabrication remains challenging. Here, we report for the first time the design and preparation of homochiral polycrystalline MOF-808 membranes for the first time. The membrane exhibits a high integrity and thin membrane thickness. Achieving homochirality through chiral amino acid postsynthetic modification, MOF-808 membranes demonstrate remarkable solvent stability. Notably, they successfully separated racemic naproxen enantiomers, achieving enantiomeric excess (ee) values of up to ∼95.0%. This work paves the way for turning achiral polycrystalline MOF membranes into high-performance chiral membranes for enantioselective separation.

19.
J Am Chem Soc ; 146(21): 14835-14843, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38728105

RESUMO

The transformation of carbon dioxide (CO2) into functional materials has garnered considerable worldwide interest. Metal-organic frameworks (MOFs), as a distinctive class of materials, have made great contributions to CO2 capture and conversion. However, facile conversion of CO2 to stable porous MOFs for CO2 utilization remains unexplored. Herein, we present a facile methodology of using CO2 to synthesize stable zirconium-based MOFs. Two zirconium-based MOFs CO2-Zr-DEP and CO2-Zr-DEDP with face-centered cubic topology were obtained via a sequential desilylation-carboxylation-coordination reaction. The MOFs exhibit excellent crystallinity, as verified through powder X-ray diffraction and high-resolution transmission electron microscopy analyses. They also have notable porosity with high surface area (SBET up to 3688 m2 g-1) and good CO2 adsorption capacity (up to 12.5 wt %). The resulting MOFs have abundant alkyne functional moieties, confirmed through 13C cross-polarization/magic angle spinning nuclear magnetic resonance and Fourier transform infrared spectra. Leveraging the catalytic prowess of Ag(I) in diverse CO2-involved reactions, we incorporated Ag(I) into zirconium-based MOFs, capitalizing on their interactions with carbon-carbon π-bonds of alkynes, thereby forming a heterogeneous catalyst. This catalyst demonstrates outstanding efficiency in catalyzing the conversion of CO2 and propargylic alcohols into cyclic carbonates, achieving >99% yield at room temperature and atmospheric pressure conditions. Thus, this work provides a dual CO2 utilization strategy, encompassing the synthesis of CO2-based MOFs (20-24 wt % from CO2) and their subsequent application in CO2 capture and conversion processes. This approach significantly enhances overall CO2 utilization.

20.
Int J Cancer ; 155(7): 1203-1211, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38712628

RESUMO

The relationship between Helicobacter pylori (H. pylori) infection and upper gastrointestinal (UGI) cancers is complex. This multicenter, population-based cohort study conducted in seven areas in China aimed to assess the correlation between current H. pylori infection and the severity of UGI lesions, as well as its association with the risk of gastric cancer (GC) and esophageal cancer (EC). From 2015 to 2017, 27,085 participants (aged 40-69) completed a standardized questionnaire, and underwent a 13C-urea breath test. Then a subset underwent UGI endoscopy to assess the UGI lesion detection rates. All individuals were followed up until December 2021 to calculate the hazard ratios (HRs) for UGI cancers. H. pylori infection prevalence was 45.9%, and among endoscopy participants, 22.2% had gastric lesions, 19.2% had esophageal lesions. Higher detection rates of gastric lesions were noted in the H. pylori-positive population across all lesion severity levels. Over a median follow-up of 6.3 years, 104 EC and 179 GC cases were observed, including 103 non-cardia gastric cancer (NCGC) cases and 76 cardia gastric cancer (CGC) cases. H. pylori-infected individuals exhibited a 1.78-fold increased risk of GC (HR 1.78, 95% confidence interval [CI] 1.32-2.40) but no significant increase in EC risk (HR 1.07, 95% CI 0.73-1.57). Notably, there was a higher risk for both NCGC and CGC in H. pylori-infected individuals. This population-based cohort study provides valuable evidence supporting the association between current H. pylori infection and the risk of both NCGC and CGC. These findings contribute to the empirical basis for risk stratification and recommendations for UGI cancer screening.


Assuntos
Neoplasias Esofágicas , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Infecções por Helicobacter/complicações , Infecções por Helicobacter/epidemiologia , Pessoa de Meia-Idade , Masculino , Feminino , Helicobacter pylori/isolamento & purificação , Adulto , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/etiologia , Neoplasias Gástricas/patologia , Idoso , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/microbiologia , Neoplasias Esofágicas/etiologia , China/epidemiologia , Estudos de Coortes , Fatores de Risco , Prevalência , Neoplasias Gastrointestinais/microbiologia , Neoplasias Gastrointestinais/epidemiologia , Neoplasias Gastrointestinais/etiologia , Trato Gastrointestinal Superior/patologia , Trato Gastrointestinal Superior/microbiologia
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